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    <title>Document</title>
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    <!-- 行类样式操作 -->
    <div style="font-size:50px" onclick = "Modify()">hahaha</div>
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<script>
    function Modify()
    {
        let element = document.querySelector("div");
        let size = parseInt(element.style.fontSize)+10;
        //element.style.fontSize = size + "px";
        element.style.cssText = "font-size:" + size + "px";
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